Receptacle for internal flame gas burner and HOB comprising a receptacle of this kind and a burner of this kind

ABSTRACT

An internal flame gas burner receptacle comprises at least one sealed cup having at least one gas inlet orifice, at least one cover provided with a central flame exit opening and conformed to cover the cup, and a calibrated space between the periphery of the cover and the rim of the cup.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a receptacle for an internal flame gas burner and a hob comprising a receptacle of this kind and a burner of this kind.

2. Description of the Prior Art

Known in the art are internal flame gas burners, that is to say gas burners having a central hollow portion usually called the “chimney” from which exit flames for heating vessels such as saucepans.

These burners, which are different from the standard peripheral flame gas burners equipping conventional cookers, are generally appreciated for their improved energy performance: for the same quantity of gas supplied, the contents of a vessel are heated much faster.

Without this list claiming to be exhaustive, examples of internal flame gas burners may be found in the following patents: FR 01 15643 (A.E.M.), FR 02 16041 (Gaz de France) and JP 10 19425 (RINNAI KK).

One particular object of the present invention is to provide means for further improving the energy performance of internal flame gas burners.

SUMMARY OF THE INVENTION

The subject of the invention is achieved with an internal flame gas burner receptacle comprising:

-   -   a) at least one sealed cup having at least one gas inlet         orifice,     -   b) at least one cover provided with a central flame exit opening         and conformed to cover the cup, and     -   c) means for maintaining a calibrated space between the         periphery of the cover and the rim of the cup.

This receptacle in accordance with the invention encloses an internal flame gas burner in a volume to which the entry of gas is totally controlled.

In particular the entry of air may be calibrated to optimize the process of combustion taking place within the burner and thereby optimize the performance of the burner.

According to other features of the receptacle:

-   -   the cover has a flame deflector shape;     -   the cover has a frustoconical region with the opening at the         bottom;     -   the cover comprises vessel support lugs.

The present invention also provides a top plate comprising at least one receptacle as defined hereinabove and a plate joined and sealed to the rim of the cup.

According to other features of the top plate, the opening is under the plate.

The present invention further provides a hob comprising a top plate as defined hereinabove and at least one internal flame burner disposed in the receptacle whose injector communicates with the gas inlet orifice and whose chimney is disposed in line with the opening.

According to other features of the hob:

-   -   the gas burner is of the compact type;     -   the burner comprises an aspiration tube situated substantially         in the plane in which the flame outlet orifices of said burner         discharge;     -   it comprises a plurality of receptacles and burners of different         sizes.

Other features and advantages of the present invention will become apparent in the light of the following description and on examining the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a hob according to the invention.

FIG. 2 is a perspective view of a top plate forming part of the FIG. 1 hob.

FIG. 3 is an exploded perspective view of one of the burners of the FIG. 1 hob.

FIG. 4 is a perspective view of one of the covers forming part of the FIG. 1 hob.

FIG. 5 is a view in section in the plane P in FIG. 1 of a portion of the hob from that figure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Refer now to FIG. 1, which represents a hob 1 according to the invention.

The hob 1 comprises a top plate 3 in turn comprising a plurality of receptacles 5 a to 5 e connected to each other by a plate 4, each receptacle comprising a cup 7 a to 7 c and a cover 9 a to 9 e.

Within each of the cups 7 a to 7 c is an internal flame burner 11; only one of the burners may be seen in FIG. 1, in a position withdrawn from the hob, as may its associated cup 7 b

Refer now to FIG. 2, which shows that the top plate 3 may be a metal plate 4 pressed to form a plurality of cups 7 a to 7 e each preferably having the shape of a slice of cake.

Alternately, the cups may be fabricated independently of each other and attached, for example welded, to a metal plate 4 joining them together.

Each cup 7 a to 7 e has a gas inlet orifice 14 a to 14 c.

Refer next to FIG. 3, which is an exploded perspective view of an internal flame burner 11 that may be used with the top plate 3 of the invention.

This burner conforms to the teaching of patent application FR 02 16041, but it must be clearly understood that this example is in no way limiting on the invention.

Briefly, this burner 11 comprises a gas injector 15, an aspiration tube 17, a pot 19, and a cap 21.

The function of the aspiration tube 17, also known as a “Venturi”, is to draw in primary combustion air, this induction or aspiration of air resulting from a pressure drop in the tube 17 caused by the gas leaving the injector 15 and being accompanied by turbulence whereby the primary air is mixed with the gas.

The cap 21 caps the pot 19 and, with the pot 19, delimits an annular chamber 23 whose internal edge 25 includes flame outlet orifices 27.

The air and the gas coming from the tube 17 finish up by mixing intimately in this chamber 23, the resulting combustible mixture being divided homogeneously and distributed to the flame outlet orifices 27, where it ignites and burns in secondary air from the surroundings.

The tube 17 extends along an axis that is substantially in the plane onto which the orifices 27 discharge and preferably has a length at most twice the radius of the internal rim 25 of this chamber.

Because of this length to radius ratio, a burner of this kind is small in the horizontal direction and may therefore be described as “compact”.

A distribution member 29 in the shape of a circular arc is disposed between the outlet of the tube 17 and those of the orifices 27 that face it.

Refer next to FIG. 4, which represents a cover 9 that may be used with the top plate of the invention.

As may be seen in this figure, this cover 9 comprises a central flame exit opening 31 which is at the bottom of a frustoconical portion 33 around which are distributed several vessel support lugs 35 a to 35 d, for example four such lugs.

The general shape of the cover 9 corresponds to that of the cups 7 a to 7 d (see FIG. 2).

All of the members just described may be fabricated from stainless steel or a similar alloy.

Refer next to FIG. 5, which shows how a cup 7, an internal flame burner 11 and a cover 9 are arranged relative to each other in an operational situation.

The burner 11 represented in this figure has a slightly different shape from that which has just been described; the invention is not limited to any particular design of internal flame burner.

FIG. 5 shows that the aspiration tube 17 is disposed in line with the gas injector 15, which is in turn disposed in the gas inlet orifice 14 of the cup 7.

The burner 11 is simply placed on the bottom of the cup 7.

A space E is formed between the periphery of the cover 9 and the plate 4, enabling air A to circulate from the exterior toward the interior of the cup 7.

The space E is obtained by any appropriate means, such as spacers (not shown) disposed between the cover 9 and the plate 4.

The chimney 37 of the burner 11, that is to say the region of the burner onto which the flame outlet orifices 27 discharge, is disposed in line with the central opening 31 of the cover 9.

The central opening 31 is under the plate 4 of the top plate 3.

The rim 39 of the central opening is curved on itself so that it has a flame deflector shape.

The mode of operation and the advantages of the invention follow directly from the foregoing description.

Refer to FIG. 5 in particular.

The cover 9 and the cup 7 form a volume that is virtually closed on the inside and into which the incoming flow of air A may be totally controlled.

In particular the space E may be calibrated so that the flow of air A optimizes the energy efficiency of the burner 11, which utilizes a portion A1 of this air as primary air (mixed directly with the gas arriving via the injector 15) and another portion A2 of this air as secondary air (incorporated into the combustion in the area of the chimney 37).

In this way the air A may be metered to reduce unburned particles in particular.

The frustoconical shape of the cover 9 lowers the bottom of the vessel to be heated relative to the plate 4, which reduces vertical bulk and is particularly beneficial from an esthetic point of view.

In particular, the burners may be practically invisible from the outside, which yields a very restrained design.

An ultra flat hob may be obtained by using an internal flame burner like that represented in the figures, that is to say of the type having an aspiration tube 17 substantially in the plane in which the flame outlet orifices 27 discharge.

The curved shape of the rim 39 of the opening 31 encourages the distribution of the flames under the vessel to be heated: thanks to this shape, the flames are first directed toward the center of the chimney 37 and then curved upward and toward the exterior of the burner.

The covers 9 a to 9 e further protect the burners and the cups from soiling by the contents of the vessels to be heated.

Taking all of the air necessary for combustion from above the cooking surface conforms to the applicable standards.

Sealing the connection of the cups 7 a to 7 e to the plate 4 prevents any accidental confinement of gas under the cooking surface.

Of course, the present invention is not limited to the embodiment described and shown.

For example, the hob of the invention could be limited to a top plate comprising only one cup and one burner.

Likewise the hob of the invention could comprise a “collective” cup and/or cover, that is to say one receiving or covering a respective plurality of burners. 

1. An internal flame gas burner receptacle comprising: a) at least one sealed cup having at least one gas inlet orifice, b) at least one cover provided with a central flame exit opening and conformed to cover said cup, and c) means for maintaining a calibrated space between the periphery of said cover and the rim of said cup.
 2. The receptacle claimed in claim 1 wherein said cover has a flame deflector shape.
 3. The receptacle claimed in claim 1 wherein said cover has a frustoconical region with said opening at the bottom.
 4. The receptacle claimed in claim 1 wherein said cover comprises vessel support lugs.
 5. A top plate comprising at least one receptacle as claimed in claim 1 and a plate joined and sealed to the rim of said cup.
 6. The top plate claimed in claim 5 wherein said opening is under said plate.
 7. A hob comprising a top plate as claimed in claim 5 and at least one internal flame burner disposed in said receptacle whose injector communicates with said gas inlet orifice and whose chimney is disposed in line with said opening.
 8. The hob claimed in claim 7 wherein said gas burner is of the compact type.
 9. The hob claimed in claim 7 wherein said burner comprises an aspiration tube situated substantially in the plane in which the flame outlet orifices of said burner discharge.
 10. The hob claimed in claim 7 comprising a plurality of receptacles and burners of different sizes. 